Study design. A prospective, quantitative study was performed to analyze characteristics of patients with IAD and fecal incontinence treated in the ICU.
Sample and setting. This study was conducted at the 3000-bed Tianjin Medical University General Hospital (Tianjin, China) from October 2016 to December 2017. A total of 266 patients was recruited from 4 ICUs (general, neurological [NICU], rehabilitation, and gerontology) using convenience sampling methods. Because the patients in these units often have complex conditions with associated immobility and incontinence, they are at high risk of developing IAD according to epidemiological data.17-20
Inclusion criteria stipulated participants must be at least 18 years old, without IAD or a pressure injury at admission, have fecal incontinence or urinary incontinence and using an indwelling catheter, and able to provide informed consent (from patient and relative). Patients hospitalized <7 days, experiencing urine leakage despite an indwelling catheter, unable to change position, or who refused study participation were excluded.
Ethical consideration. The study purpose and method were explained to the patients, and their informed consent was obtained. When it was difficult to obtain informed consent from the patient, it was obtained from the patient’s legal guardian. The study was approved by the Ethics Committees of the General Hospital of Tianjin Medical University (IRB2018-YX-081).
Research variables. Demographic data (age, gender, and ICU type) were collected from the patients’ medical records on admission. Data on length of hospitalization in the ICU were collected after discharge. Data related to fecal incontinence (Perineal Assessment Tool [PAT] scores, bowel movement frequency, and stool traits per the Bristol Stool Scale) were obtained within 24 hours after the first episode of fecal incontinence. Clinical data (body temperature, diabetes history, hypertension history, consciousness, nutritional support, oxygen supply, number of antibiotic species, sedative use, and albumin levels) were collected at the same time as the fecal assessments. Specifically, axillary body temperature was obtained and recorded at 8:00 am for patients with fecal incontinence. Fever was defined as temperature ≥37˚C (normal range is 36˚C to 37˚C21). Information on diabetes history, hypertension, and sedative use was collected from clinician records. According to Yang et al,22 antibiotic use can lead to diarrhea, so the number of antibiotic species (based on the treatment plan and the pharmacopoeia) was included in the risk factor assessment. Data on consciousness, nutritional support, and oxygen supply were collected from medical records. Hypertension was defined as follows: first-grade hypertension was noted as systolic blood pressure of 140 mm Hg to 159 mm Hg and/or diastolic blood pressure of 91 mm Hg to 99 mm Hg; secondary hypertension was noted as systolic blood pressure of 160 mm Hg to 179 mm Hg and/or diastolic blood pressure of 100 mm Hg to 109 mm Hg; and tertiary hypertension was defined as systolic blood pressure 180 mm Hg and/or diastolic blood pressure ≥110 mm Hg.23 Patient albumin level <35g/L 24 hours after the first episode of fecal incontinence was defined as “less than normal” (lower than the normal range of 35 g/L to 50 g/L).24
Care and data collection procedures. A paper-and-pencil questionnaire was used to collect sociodemographic and clinical data. Patient names were coded anonymously. Data collection was completed by 5 nurses; a qualified wound and ostomy therapist was in charge of supervision and 4 experienced ICU nurses from each ICU were responsible for collecting data. At the beginning of the study, the 5 nurse investigators simultaneously were trained on variable measurement and how to use the assessment tools. The 4 investigators in each unit conducted a daily evaluation of all patients to help ensure accurate data acquisition. If an incident of fecal incontinence occurred, the study investigators recorded the research data within 24 hours.25 The qualified wound and ostomy therapist was responsible for supervising the evaluation to ensure data quality.
Patients with fecal incontinence were provided standard incontinence care from trained nurses that included cleaning the area contaminated by feces using warm water and changing the diaper and/or contaminated bed units, along with regular cleaning of the perineal area. The nurses on duty routinely performed skin assessment and care every 2 hours for all patients.26
PAT. The PAT is a predictive tool for assessing the risk of developing IAD in patients with incontinence.27 The PAT evaluates risk according to 4 factors and each factor is assessed using 1 to 3 points: the type and intensity of the irritant (1 = formed feces and/or urine, 2 = soft feces and/or urine, 3 = liquid feces and/or urine), the specific amount of time the skin is exposed to irritant (1/2/3: sheets/diapers replaced at least every 8/4/2 hours), the specific condition of genital skin (1 = clean and complete, 2 = erythema/dermatitis, 3 = exfoliation and erosion of skin), and related factors leading to diarrhea (1/2/3: zero to 1/2/3 or more related factors). The total score ranges from 4 to 12. Higher scores represent a greater risk of developing IAD. The PAT score can be divided into low risk (total score <7) and high risk levels (total score ≥7).
Xie et al28 reported the Cronbach-α value and interrater reliability of the PAT were 0.512 and 0.882, respectively, among Chinese incontinent patients.
Bristol Stool Scale. The Bristol Stool classification, developed by Lewis and Heaton,29 divides stool into 7 types. The first and the second type indicate constipation. The third and the fourth type indicate ideal shape (soft, sausage-shaped, and easy to defecate). The fifth (soft, semisolid, small, uneven edges), sixth (fluffy pieces with ragged edges or mushy), and seventh types (watery/no solid pieces/entirely liquid) indicate the possibility of diarrhea.29 A reliability and validity survey by Blake et al30 concluded this scale showed substantial validity and reliability.
The investigators evaluated the stool traits using Bristol scale reference pictures. The stool trait was identified as the most common recurring stool type for each patient. The frequency of patients’ bowel movements was observed over 24 hours after the first episode of fecal incontinence.
Data analysis. All data were entered into SPSS, version 20.0 (IBM Corporation, Armonk, NY) software. Descriptive statistics were used to describe frequency, percentage, mean, and standard deviation. Univariate analysis, including the chi-squared test and 2 independent sample t tests, were performed to detect differences among characteristics. Researchers compared the difference between patients with and without IAD among the following factors: age, gender, body temperature, diabetes history, ICU hospitalization, ICU type, coma, sedative use, hypertension history, nutritional support, oxygen supply, number of antibiotic species, PAT score, albumin level, frequency of bowel movements, and stool traits. Binary classification logistic regression was used to analyze the independent risk factors for IAD if a significant difference was noted in univariate analysis. Logistic regression was applied as needed based on model assumptions, and odds ratios were used to quantify the magnitude and direction of any significant associations.
The significant risk factors (P <.05) from bivariate analysis then were included in a process of stepwise selection to determine the group of strictly significant variables31; forward selection was utilized to determine a predictive model. The sensitivity, specificity, and accuracy of the model were analyzed, and the prediction effect of the model was evaluated using the receiver operating characteristic (ROC) curve. All analyses were 2-sided, with a significance level of .05.